Surface Modified β-Tricalcium Phosphate Enhanced Stem Cell Osteogenic Differentiation in Vitro and Bone Regeneration in Vivo

Abstract

In vitro, in vivo, and clinical studies had demonstrated Beta-tricalcium phosphate (β-TCP) biocompatibility, bioactivity, and osteoconductivity in bone regeneration. The present research aimed to enhance β-TCP's biocompatibility and physical and chemical properties by argon plasma surface treatment without surface modification. Treated β-TCP characterization was done by scanning electron microscopy (SEM), energy-dispersive spectrometry, X-ray photoelectron spectroscopy (XPS), X-ray diffraction analysis, and Fourier transform infrared spectroscopy characterization. The viability of human mesenchymal stem cells (hMSCs) and osteoblastic differentiation were determined by water-soluble tetrazolium salts-1 (WST-1), immunofluorescence, alkaline phosphatase (ALP) assay, and quantitative real-time polymerase chain reaction. The results indicated a slight enhancement of the β-TCP by argon glow discharge plasma (GDP) sputtering, which resulted in a higher Ca/P ratio (2.05) than the control. Furthermore, when compared withcontrol β-TCP, we observed an improvement of WST-1 on all days (p < 0.05) as well as of ALP activity (day 7, p < 0.05), with up-regulation of ALP, osteocalcin, and Osteoprotegerin osteogenic genes in cells cultured with the β-TCP test. XPS and SEM analyses indicated treated β-TCP’s surface was not modified when impurities were removed. In vivo, micro-computed tomography and histomorphometric analysis indicated that the β-TCP test managed to regenerate more new bone than the β-TCP control and was able to control defects at 8 weeks (p < 0.05). Argon GDP treatment is a viable method for removing macro and micro particles of <7 μm in size from β-TCP bigger particles surfaces while improving its biocompatibility with slight surface roughness modification, enhancing hMSCs proliferation, osteoblastic differentiation, and stimulating more new bone formation.

Magnesium Modified β-Tricalcium Phosphate Induces Cell Osteogenic Differentiation In Vitro and Bone Regeneration In Vivo

“…Later, nuclear counterstaining was conducted using DAPI (0.1 µg/mL; 4 ,6-diamidine-2 -phenylindole dihydrochloride; D9542 Sigma-Aldrich Chemie GmbH, Deisenhofen, Germany) for 10 min; subsequently, after staining, 200 µL of phalloidin solution was counted for 15 min. Finally, labeled particles were investigated in 24-well plates operating an Fv-1000 laser scanning confocal microscope (Olympus Corporation, Japan) in conjunction with a high power 40× objective lens and analyzed by Leica LASX software [51].…”